Igor Kratskin, MD, PhD

My current research focuses on
investigating the physiological role of the amino
acid taurine in olfaction.

Taurine is abundantly present in the olfactory epithelium
and olfactory bulb; however, its function and the
sites of biosynthesis in these structures remain unknown.

We developed antibodies to a taurine-synthesizing
enzyme and carried out immunohistochemical studies
in rats.

Results of these studies suggest that olfactory sensory
cells and various types of bulbar neurons are involved
in taurine production.

Electrophysiological studies in slices of rat olfactory
bulb showed that taurine, by activating GABAA and
presynaptic GABAB receptors, produces inhibition of
principal neurons,
mitral and tufted cells, and reduces their synaptic
responses to olfactory nerve stimulation, but has no
effects on
local interneurons, periglomerular and granule cells.

This suggests that taurine may serve to protect principal
neurons of the bulb from hyperexcitation.

Olfactory sensory neurons, due to their proximity
to the external environment and continual replacement
throughout life, may require the presence of taurine,
which acts as a potent cell-protecting and neurotrophic
factor.

To test this hypothesis, we employ antisense technology
in order to inhibit local translation of the taurine-synthesizing
enzyme from specific mRNA and produce taurine deficiency
in the olfactory epithelium.

This project is entitled "Function of Taurine
in the Primary Olfactory Pathway" and supported
by the NIH Grant RO1 DC04083 (award period: 2/01/20001/31/2004).